Finally, materials that help you meet this part of the educational standards and comparative assessments! Under the guidance of a professional math detective, students gradually discover mathematical patterns, structures, and laws. Using well-known exercise formats such as number chains, number walls, and mirror tasks, they deepen their calculation skills and gain an initial, child-friendly approach to exploring, hypothesizing, and justifying mathematical relationships. Through the challenging tasks set by the math detective, targeted questioning, and joint foundational work in the form of a detective lexicon, students gradually develop systematic approaches to problem-oriented tasks. By documenting their investigative results in a detective notebook, they also enhance their mathematical skills.